Perhaps you should try some spelling variations:
sang mai » sang ma, sang tai, lang mai
mai khoi » mai khoa, tai khoa, cac khoi
kinh ve » kinh te, dinh ve, minh ve
va kinh » va tinh, qua kinh
hieu va » lieu va, hieu qua
sach ly » sach y, sach ty, sach hay
hieu ve » hieu van
sach lo » sach dao, sach doi, sach hoi
xuc va » duc va, tuc va, luc va
ve cua » le cua, de cua, te cua
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ly) or (sach lo)) sang mai khoi. ((hieu ve) OR (hieu va)) cam xuc va kinh ve cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ly) OR (sach lo)) sang mai khoi. ((hieu ve) OR (hieu va)) cam xuc va kinh ve cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ly) or (sach lo)) sang mai khoi. ((hieu ve) OR (hieu va)) cam xuc va kinh ve cua te".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ly) or (sach lo)) sang mai khoi. ((hieu ve) OR (hieu va)) cam xuc va kinh ve cua te*.